CURL-通过TLS连接显式FTP

Question

I am trying to connect to FTP server using encryption as explicit FTP over TLS.

curl_setopt($ch, CURLOPT_URL, 'ftp.mydomain.com/orders'.$filename);
curl_setopt($ch, CURLOPT_USERPWD, 'uname:pwd');
curl_setopt($ch, CURLOPT_UPLOAD, 1);
curl_setopt($ch, CURLOPT_INFILE, $fp);
curl_setopt($ch, CURLOPT_PORT, 21);
curl_setopt($ch, CURLOPT_INFILESIZE, filesize($localfile));
curl_exec ($ch);
$error_no = curl_errno($ch);

I have to upload the file to this location, but while connecting to the server, it gives the error number 56 (response reading failed). I am not sure whether I am using the correct options to explicitly connect FTP over TLS.

Answer 1

Not only you didn't enable TLS/SSL. You didn't even specify what protocol to use. And CURL defaults to HTTP. So your code fails because CURL tries to talk HTTP to FTP server.

To select FTP and force TLS/SSL:

curl_setopt($ch, CURLOPT_PROTOCOLS, CURLPROTO_FTP);
curl_setopt($ch, CURLOPT_FTP_SSL, CURLFTPSSL_ALL);

Answer 2

Try with below code -

curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
curl_setopt($ch, CURLOPT_FTP_SSL, CURLFTPSSL_TRY);
curl_setopt($ch, CURLOPT_FTPSSLAUTH, CURLFTPAUTH_TLS);